Q1...T/F

1) if n small drops each of surface charge density of charge  coalesce to form a big drop then the surface density of charge of conducting drop is .

2) a ring of radius R carries a uniformly distributed charge +Q. a point charge -q is placed on the axis of ring at  a distance 2R from the center of the ring  and released from rest.the particle executes SHM along the axis of ring .                      (if ans.=True,calculate time period of oscillations).

Q2.....More than one choice can be correct

1) each plate of a parallel capacitor has charge q on it .the capacitor is now  connected to a battrey.now,                 

a)the facing surfaces of  the capacitor have equal and opposite charges.                      

b)the two plates of  the capacitor have equal and opposite charges.

c)the battery supplies equal and opposite charges to the plates.

 d)the outer surfaces of  the plates have equal charges.

Q3...what will be the graph for magnetic field along the axis of solenoid?       ( with  explanation)

1) quick answer

dimension of final surface charge density is not true.

2)by calculation:-

final R of drop is rn^1/3. =Q/r². on doing this 4 final drop its n^-2/3

so F

acc. to key;

1) .....answer to this question is  (TRUE).

2)......answer is false.

3)......a,c,d